Tuberculosis in Brazilian prisons

Tuberculosis (TB) in people deprived of liberty (PDL) in Brazil is 28 times higher than the general population. Prison environment favours spread of the Mycobacterium tuberculosis and drug-resistant TB. Objective: To describe TB transmission dynamics and drug resistance profiles in PDL through whole genome sequencing (WGS). Methodology: Retrospective study of Mycobacterium tuberculosis isolates cultured from PDL while incarcerated between 2016 to 2019. The PDL mobility information between prisons was obtained from the penitentiary administration system (SAP). Clinical information was collected through the official report system. WGS was performed on clinical Mycobacterium tuberculosis isolates taken at the time of TB diagnosis using the Illumina NextSeq500 and phenotypic drug-susceptibility testing (DST) was done using the non-radiometric method in liquid medium, BACTEC 960 MGIT. Results: Most of the 134 PDL with TB (97.8%) were male with a mean age of 30yrs. Four patients had confirmed HIV. A hundred and two (76%) were new TB cases and 32 (24%) had a record of previously treated TB. WGS analysis detected 16 clusters consisting of 2-7 isolates (=5 SNPs) suggesting recent transmission among 58 (43%) PDL. Six (4,4%) isolates showed resistance to at least one anti-TB drug. Of these, two were clustered and showed resistance to rifampicin, isoniazid, and fluoroquinolones with 100% concordance between molecular and phenotypic DST. PDL showed great mobility within the prison system and the number of different prisons for each PDL was as high as eight between 2016-2019. Conclusion: WGS of patient isolates demonstrated ongoing transmission within prisons in Brazil. The movement of PDL between different prisons has the potential to exacerbate transmission between prisoners. Furthermore, the housing of PDL in open or semi-open facilities may contribute to the transmission of TB in the community.